Driving mechanism for electrically-propelled vehicles.



mmom. `DRIVING MECHANISM FOR ELECTRIGLLY PROPELLED VEHICLES.

APPLIATION FILED AUG. 24, 1910. ggp, Patameed July 9, 1912 4 SHEETS-SHEET 1.

J. KROHN.

DRIVING MECHANISM FOR ELBOTRIGALLY PROPELLBD VEHICLES.

APPLICATION FILED AUG. Z4, 1910. j ,gggu atented July 9, 1912,

4 SHEETS-SHEET 2.

J. KROHN, DRIVING MCHANISM FR ELECTRICALLY PIROPELLED VEHICLES.

APPLICATION FILED AUG. 24, 1910.

Patented July 9. i912.

4 SHEBTSYSHBBT sl gli l (lill/1,

Il', n

J, KROH'N.

DRIVING MEGHANISM POR ELEGTRICALLY PROPELLED VEHICLES. APPLIOATION FILED AUG. 24, 191.0. LGQQQQE Patented July 9, 1912 4 SHEETS-SHEET 4.

l Mv

"Unirse stares ramena orribili.,

lOl-IN KROI'IN, CHICAGG, ILLINOIS.

DRIVING MECHANISM FOR ELECTRIGALLY-PROPELLED VEHICLS.

i ,canoes only in relative dimensions for the various applications.

Among the salient objects of the inven-l tion are to provide a driving mechanism containing the fewest possible parts necessary to etlv'ect a reduction ot the high speed "dimensions of the gearing;

of the electric motor to the relatively low rotative speed of the wheels; to embody this mechanism in such small dimensions of parts and compact form as to enable the same to be inclosed within motor housing or casing without materially increasing the 'dimensions of the same; to inclose,all the working parts in a dust and dirt-proof compartment in which the gears can, run in an oil bath so as to reduce wear and tear to a minimum and eliminate the noise due to the outside chains and gears, as iu other conJ structions; to provide a mechanism in which the gear ratio can be altered'according to requiren'ients without materially altering the to provide a mechanism having the form and character of a/ complete unit which can be handled as such, and which can completely replace other and lniore'complicated mechanisms in existing constructions; to provide a mechanism which permits of the car being washed without danger of ooding the driving mecha-nism with water; to provide a driving'mechanis'm which can be manufactured economically, which will retain the orig-j nal alinement of the parts to one another indefinitely, and which cannot be distorted in service by an uneven road surface; and to provide a mechanism permitting the use either of a single motor to drive both hind wheels, or individual motors to drive two or all of thewhee'ls of a vehicle separately.

With these and other minor objects in -view the invent-ion consists in the novel construction and arrangement of parts hereinafter described and more particularly pointed out in the claims.

Practical forms in which my invention Specification of Letters Patent. Application mea ugus'a 24, 1910. serial No. 578393.@

Patente illy 9, MM2.

may be embodied are shown in the accom panying drawings, in which- Figure 1 is an elevational view, partly in section, of a rear axle structure and wheels, showing my inventionas embodied in a construction employing a divided floating axle and a single motor driving both wheels. Fig. 2 is an enlarged axial section through that portion of the rear axle structure carrying themotor, driving gear, and Adifferential or .balance gear.' Fig. 3 is a vertical .transverse section on the line 3-8oi Fig.

2. Fig. i is a similar cross section the line -ll of Fig. 2. Figs. 5 and 6 are fragmentary plan and elevational views, respectively, in cross section through one'of the transverse 'supporting webs of the casing showing the mechanism for confining the driving member of the speed reducing gear against rotation while permitting gyratory motion thereof. Fig. 7 is a cross .sectional view through the spur differential or com-- pensating gear; and Fig. 8 shows a modification wherein an independent motor is applied to each wheel,

Referring to the drawings, 10 designates the two rear wheels of an electrically propelled vehicle, and 11 the hollow bridge or gear and axle casing which, in this instance, is made sufliciently large to accommodate not only the differential Or balance gear but yalso the motor and the driving connections between the armature. shaft of the motor and' the differential gear.l Rigiflly secured to and within the ends of the casing 1-1 are t-he end axle casings or tubes 12 supporting the inner stationary bearing rings 13 of the usual ball-bearings 14, the outer bearing rings-15 being fast with rnd carried by the hubs 16 of thewheels. K

The hollow casing 11 is provided with a plurality of rigid transverse webs 17, 18, 19, and 20 (Fig. l). In and between the webs 17 and 18y is rotatably mounted by ball-bearings 21 a hollow driving shaft 22, whichloosely surrounds one section 23 of the divided, floating axle, he other section of said axle being shown at 24; the inner meeting ends of said axle sections are squared as shown at 23a and 24, respectively', (Fig. 2)' and have mounted thereon the two main spur Wheels of the diierenti-al gear, as more fully'hereinafter described; said axles attheir 'outer ends extending through thefjstationary end 'axle casings l2 and beingdri'vngly ,connecte `,throughspi; f'

ders to the hubs of the Wheels', said s iders and the bearings being protected fy dustecaps 26 screwed on to the outer ends -et the hubs. l

Fast onthe hollow driving shaft 22 is'the armature 2,7 of an electric motor, the field whereof is indicated at 28. The shaft 22 is provided at one end with an`integral eccentric head 29, preferably made hollow for the sake ol lightness; and on this eccentric head is mounted, through the agency of an ordi# nary anti-friction or ball-bearing 30, the driving member. 3l of the speed reducing driving gear. This latter comprises the internal member 3l formed on its periphery with il-shaped teeth and the outer driven member 32 'which has on' its inner periphery similar V -shaped teeth, but dilt'ering in number :trom thcteeth on the member 31,

the inner member having, say sixty teeth, and the outer member say sixty-four teeth; although the ratio ot the teeth may be hat 'ed with a corresponding change in the be speed increasing with i z. ii'e .nce in the number by the respective gear mem be l diameter of the outer me, )er eivhat greater than the external diameter of the inner member 31, and the tiro are at all times in slightly eccentric relation to each other. The inner gear member 31 is comined against rot-ation hut permitted. a gyratory or circular sweeping increment within the outer gear member by means of a connection to the web 18 of suoli a character that it may have a bodily radial movement in any direction;'the connect-ion herein shown comprising a disk 33 that is provided on one side with a pair of diametrically opposite radial grooves 34 and on its opposite side with a similar pair ot diametrically opposite radial grooves 35 located 9() degrees 'from the grooves 34; and keys 3G and 37 carried by the' gear member 3l and the stationary web 18, respectively, slidably engaging said grooves.

The outer gear member 32 is rigidly scoured within and carried by an annular vflange 38 formed on one end of the ditl'crential box or easing 89, said flange being mounted .tor rotary movement through an anti-rictioinbearing 40 in the transverse web 19 of the axle bridge. The other end of the diilerential gear box or casing 39 is.

formed with a hub Zll-which is rotatably` mounted through an anti-friction bearing 42 in the transverse web 20. The differential or compensating gear herein shown isv the ordinary type ot spur gear dill'erential, comprising` essentially the main gears 43 and 44 fast on the squared ends of the axle sections, and a plurality of pairs ot' spur pinions 45 and 46 rotatably moun -fl on shafts 47 and 48 journaled in the end Walls of the di'tl'erential casing, the pinions 45 meshing with the gears 48, pinion/s 46 meshing with the gears 44, and the two pinions being made of such length as to overlap and mesh with each other between the main gears 43 and 44.

The operation will. be apparent from the foregoing description of the structure of the mechanism, but may be briefly described as follows. The current being supplied to the motor, the rotation of the armature ata rapid speed imparts a similar rotation to the hollow driving shaft 22 secured thereto and to the eccentric 29. The eccentric imparts a rapid gyratory or sweeping movement to the inner gear memberl, which latter, by reason of having a less number of teeth than the outer gear member 32, imparts a rotation, at a greatly reduced speed, to the latter, said outer gear 32, through the differential. gear, transmitting this reduced speed to the axle sections, which latter transmit the rotary movement tothe wheels. The type of combined driving and speed reducing gear herein shown has a number ot advantages. In the first.- place, the entirev `Ireduction of speed is etico-ted. through the use of but tif/o gears. The gearing is economical of power, since friction between the gear teeth is practically eliminated. The, V-shaped gear teeth are of simple form and easily and economically manufactured. The speed ratio, which is approximately 1 to 16 in the structureas herein shown,'can easily be changedby substituting either an inner or outer gcarmenr' ber having a dilierent number of teeth and without requiring any change in diameter of either. Y.

In F ig. 8 I have shown an application of the invent-ion wherein the Wheels are driven each by an independent motor, which arrangement, 'of (iourse, dispenses with the necessity of a dilicrent-ial gear. inthis construction thestationary axle bridge 50 is formed with a compartment which is housed the lield 28 and armature 27 of the motor, the latter being on the hollow driving shaft 22. Said driving shaft is rotatably supported in an anti.

friction bearing 21 carried by the transverse web 18 ot the casing, and. has integral with or keyed to one end an eccentric 29 supporting, through anti-friction bearings 30', the inner gear member 31 ot the driving and speed reducing gear. The cop erating outer gear member 32 is rigid with and carried by a llanged disk 52, the hub 53 of which latter is journalcd by antifriction bearings 54 in a transverse web 20 of the casing, said hub being keyed on the inner `end of the floatingk shaft 55, thislatter being drivingly connect-ed at its outer end to the hub of the Wheel in the manner and by the means already described in con- 51 at each i 'end adjacent to the wheel hub, within ion .attained in the mechanism described.

tion of speed is edected through e tranmis sion gecr of extreme simplicity and e practically rictioni character; the Usui-.i reer axle bridge, by n slightenlargement, is mede to serve easing and protection not only for the differential gear (when eniployed) but for the motor and transmission und speed reducing geni' es Weli; und he construction is cepnhie of being masonictured economiceliy, pitch ret-io may be vsried ss desired by the simple substitut-ion an inner or outer .weer member having e different number of reeth. It will be apparent to those skilled in the ort that the details of the structure, es shown end described, may be considerably varied, wiihont involving any essentiel change in the character of the mechanism and the results secured thereby, and hence I do not limit the invention to the partienier embodiment thereof disclosed, ceptto the extent clearly indicated in specific cioiins.

l cieinie l., In e power driven vehicle, the combi.- nation of driving nxlesections each connecting ai its enter end with the vehicle drivey housing eoncentricsiiy disposed about seid axle lsections and supported from said drive wheels, e differential transmission 'train within scid housing surrounding the inner ends of s nid axle sections and connected therewith nt one end, :i rini at'thc other end of said transmission trein con-- centric with said unie sections and having intel-nal transmission teeth, n sleei'e concentric with said axle sections and having e bearing hond eccentric with snidnxle sections und disposed within seid rim, c second rim 1 wheel, n

concentricsiiy join'nniedon seid eccentric head und inning external teeth of n digen ent, number than than; of the teeth on theliirst mentioned rim, ineens for prevent' eniei rotation of said second rim about soifY head, ond on eiectric motor having' ne. mounted concentricoiiy Within seid-bons about said sleeve and haring its robin eiement connected driving' rention nu, seid sleeve, rotation of seid sieeve and centric need redini displncemeo of seid second and redini engagement the teeth there-oic with the in-ernni teeth the first mentioned rire whereby' .the sections nre drie that of the sieeve 2. in c power rives vvehicle, the cerchi eiion oi? driving exie sections conneJ4 ing :it its enter end *wenn Vehicle drive 'wheei7 n housing coneeniriceiiy disposed et speed different from eide. .7

about said orale seciions end stinnerted j, e 1. Rr 1 rroni seid. drive wheeis, n' ciierentiei transmission trein" Within seid housing son rounding the inner ends of seid oX'le sec.- tions and connected therewith et one end, a rim atv the other 'endoi seid. trensmission train concentric with seid :nde sections having internal.-transinission ideeth n sleeve concentric with seid szde sections end heving n bearing heed eccentric with said sections and disposed Within said rim, s haii bearing mounted on seid eccentric heering head, :i second rim encirciing said hell beering and having externei iieeh oi3 dideren number than that of theteeth on the first menioned rim, ineens for preventing asiel roetion of seid second rim shout- :nnd en electric meier having its. parte mounted concenricnii-y within seid housing' @bout seid sleeve and having its rotating element connected seid sleeve, rotation of seid sleeve and eccentric hemd causing redini cispieceznent of seid second rim end redini engagement, ofv the teeth thereof Wiih the internal vteeth of the first mentioned. rim whereby the angie sections cre driven et a speed diiieren from thaty ofthe sleeve axle. V

JUE?! l'IRUHN, iiitnesses:

NELLE E. neneonn, f1 :1 1

'comme J @crie/nom in drivingirelatin with .seid heed, 

